1. Field of the Invention
The invention relates to an accelerator pedal and brake system for use in vehicles such as rider mowers.
2. Description of the Prior Art
Many conventional belt-driven rider mowers provide driving controls that include a hand actuated lever for selecting the forward or reverse mode, a hand actuated lever for selecting the speed of travel, and a foot actuated clutch pedal which acts to override the speed select lever. The operator begins the mowing operation by starting the mower's engine while the speed select lever is in a neutral or non-driven mode. The operator then initiates forward progress in one of two ways. First, he may slowly shift the speed select lever to a desired speed without depressing the clutch pedal. As the operator shifts the speed control lever a linkage connected to the speed control lever causes an idler arm to swing an idler pulley into a belt, thus causing a variator pulley to be adjusted, as generally described in U.S. Pat. No. 4,771,856. The adjustment of the variator pulley increases the rate at which power is transmitted to the driven wheels, thus increasing the vehicles ground speed. Secondly, the operator can move the speed select lever to a desired setting while depressing the clutch pedal, and then gradually release the clutch pedal to cause the vehicle to assure the desired speed selected by the speed select lever. The clutch pedal is connected via a linkage to the idler arm such that when the clutch pedal is depressed the variator pulley will assume a non-driven mode, regardless of the position of the speed select lever. Some mowers utilize a lost motion coupling between the clutch pedal linkage and the idler arm that allows the clutch pedal to override the speed select lever. As the speed select lever is shifted from a neutral to a driven position when the operator is depressing the clutch pedal, the vehicle remains non-driven. When the operator releases the clutch pedal the variator pulley is allowed to assume the position corresponding to the position of the speed select lever.
Once the desired speed has been attained, the vehicle may be slowed or stopped in a number of ways. The operator may shift the speed select lever to a slower or non-driven setting. The operator may also depress the clutch pedal to slow the mower. When the operator wishes to again increase speed to the predetermined level he releases the clutch pedal and the vehicle resumes the rate of travel corresponding to the position of the speed control lever. Finally, the operator may slow or stop the mower by depressing a brake pedal. Some mowers of this type provide a tab connected with the brake pedal behind and in confronting relation with a tab connected with the clutch pedal. As the operator depresses the brake pedal the brake pedal tab engages the clutch pedal tab, which causes the clutch pedal to be actuated automatically as the operator depresses the brake pedal. These vehicles thereby assume a non-driven mode when the operator engages the brake pedal to stop or slow the vehicle.
Some of these mowers are provided with a parking brake feature. To apply the parking brake the operator depresses the brake pedal fully and shifts a parking brake lever that acts to maintain the brake pedal in its engaged position. When the parking brake is being used the tabs between the brake pedal and the clutch pedal act to keep the clutch pedal depressed such that the operator can not unintentionally drive the vehicle when its parking brake is applied. This prevents the vehicle, and particularly the brake mechanism, from being damaged by driving the vehicle when the parking brake is applied.
This type of conventional mower allows for normal mowing operation without requiring the operator to manipulate any controls unless he desires to stop mowing or slow the vehicle when mowing around obstacles. Therefore, these vehicles do not provide for an operator presence feature that automatically stops the vehicle when the operator has left the mower. Many of these vehicles allow the operator to shift between the forward and reverse modes while in a driving mode, which can cause damage to the vehicle. These vehicles generally make no provision for the speed to be limited while in the reverse mode. Also, the pedal and lever configuration may not be familiar to the average person and may require a certain level of operator expertise. The pedals and levers permit the operator to change the speed of the mower by moving the hand actuated lever without depressing the foot actuated clutch pedal. This method of varying the speed can be difficult and can cause the mower to lurch or jerk as the lever is moved abruptly.
Another type of conventional rider mower utilizes an accelerator pedal to select a desired speed for the vehicle. These mowers also include a brake pedal to slow or stop the vehicle and a hand actuated lever that selects the mower's forward or reverse mode. Many of these mowers allow the operator to shift between the forward and reverse modes while the vehicle is being driven, which can cause wear to the vehicle. Many of these mowers allow the vehicles to be driven in reverse at a rate equal to its rate of travel in the forward mode. It is known to provide such mowers with a parking brake, but many such mowers allow the accelerator pedal to be depressed while the parking brake is engaged. This allows the vehicle to be driven with the parking brake on, which may eventually damage the vehicle.
Many of these vehicles provide an accelerator pedal comprised of a flat surface on which the operators foot rides. These pedal surfaces, much like an automobile's pedals, are generally larger than the brake pedal surfaces so that the operator can easily differentiate between the two. To manipulate the accelerator pedal, the operator must bend his ankle through an arc corresponding to the arc through which the pedal surface travels. In many cases, this arc is so great that the operator must bend his ankle to an uncomfortable degree or lift his heel from the operator station floor when the pedal nears either of its extreme positions. When the operator lifts his heel the speed of the mower can be difficult to regulate and the operator can become fatigued easily. Some pedals travel through a smaller arc in an attempt to eliminate the extreme angles that the ankle must accommodate, but because of this smaller arc it is more difficult to finely adjust the vehicle speed.
Another type of rider mower provides for two accelerator pedals: one for the forward direction and the other for the reverse direction. The operator begins by starting the engine, and initiates forward movement by depressing the forward accelerator pedal with his foot. The operator depresses the pedal to a point corresponding to a desired speed, and the operator must continue to depress the pedal to maintain that speed. An operator presence feature is thereby provided since the vehicle will come to a stop after the accelerator pedal is released. When the operator wishes to back up the vehicle he must remove his foot from the forward pedal to depress the reverse accelerator pedal. The operator is thereby prevented from shifting from the forward to the reverse mode while the mower is being driven, since the wheels are not being driven when the operator lifts his foot from the forward pedal to the reverse pedal. The reverse speed can be limited in this type of mower by restricting the range of motion of the reverse accelerator pedal. Parking brakes have been provided on this type of mower, and have provided mechanisms for preventing the mower from being driven while the parking brake is engaged. A mower having this type of pedal arrangement is unfamiliar to many first time users and requires a certain level of operator expertise.
Another type of rider mower provides an accelerator pedal that causes the vehicle to be propelled forward when the operator depresses the forward end or toe of the pedal, and propels the mower in the reverse direction when the operator depresses the rear end or heel of the pedal. Mowers of this type may also be unfamiliar to first time users and require a threshold level of operator expertise. This type of pedal arrangement can also be difficult to operate over rough terrain since the operator must hold his leg above the floor of the operator station with his foot positioned on the movable pedal. The operator therefore lacks the stability that would be available if he were able to keep part of his foot on the floor of the operator station.